for(int i = 0;i<len;i++){ DataBack[i] = waveform->waveP[i]; }
时间: 2024-05-27 17:10:20 浏览: 8
这段代码是一个 for 循环语句,用于将一个长度为 len 的数组 waveform->waveP 中的每个元素复制到另一个数组 DataBack 中。具体来说,循环变量 i 从 0 开始,每次增加 1,直到 i 等于 len-1 为止。在循环体中,通过下标索引将 waveform->waveP[i] 的值赋给 DataBack[i]。这段代码可能用于在某个函数中将音频波形数据从一个数组复制到另一个数组以备份或处理。
相关问题
waveform->waveP[i];
这是一个 C/C++ 语言中的数组访问操作,假设 waveform 是一个数组名,i 是一个整型变量,则 `waveform->waveP[i]` 表示取出 waveform 数组中第 i 个元素的值,其中 `->` 是结构体指针操作符,表示访问结构体指针所指向的结构体中的成员。通常情况下,结构体指针所指向的结构体中包含了一个名为 waveP 的数组。因此,`waveform->waveP[i]` 实际上是访问结构体指针所指向的结构体中的 waveP 数组的第 i 个元素的值。
检查下面的代码,找出错误病修改:public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { //以下是正确内容 OpenFileDialog openFileDialog = new OpenFileDialog(); WaveFileReader waveFileReader; DialogResult dialogResult = openFileDialog.ShowDialog(); waveFileReader = new WaveFileReader(openFileDialog.FileName); waveViewer1.WaveStream = waveFileReader; WaveFileChunkReader waveFileChunkReader = new WaveFileChunkReader(); waveFileChunkReader.ReadWaveHeader(waveFileReader); byte[] buffer = new byte[2048]; waveFileReader.Read(buffer, 8, buffer.Length); byte[] halfbuffer = new byte[1024]; // 将buffer1的内容平均除以2并复制到buffer2中 for (int i = 0; i < halfbuffer.Length; i++) { halfbuffer[i] = (byte)(buffer[i * 2] / 2 + buffer[i * 2 + 1] / 2); } //作业:使用GDI+把halfbuffer的数据绘制到panel里去。 } public class chunk { public List<char> ID; public int size; public List<Byte> Data; } private void waveViewer1_Load(object sender, EventArgs e) { } private void panel1_Paint(object sender, PaintEventArgs e) { byte[] halfbuffer = new byte[1024]; // 将buffer1的内容平均除以2并复制到buffer2中 for (int i = 0; i < halfbuffer.Length; i++) { halfbuffer[i] = (byte)(buffer[i * 2] / 2 + buffer[i * 2 + 1] / 2); } Graphics g = e.Graphics; int panelHeight = panel1.Height; int panelWidth = panel1.Width; Pen pen = new Pen(Color.Black); // Calculate the distance between each point float pointDistance = (float)panelWidth / halfbuffer.Length; // Scale the heights so they fit into the panel float heightScaling = (float)panelHeight / 256; // Draw the waveform for (int i = 0; i < halfbuffer.Length - 1; i++) { float x1 = i * pointDistance; float y1 = halfbuffer[i] * heightScaling; float x2 = (i + 1) * pointDistance; float y2 = halfbuffer[i + 1] * heightScaling; g.DrawLine(pen, x1, y1, x2, y2); } } }
在panel1_Paint方法中,buffer数组没有定义,需要在方法中声明并且赋值。可以将byte[] halfbuffer = new byte[1024]; 语句移到panel1_Paint方法内,并在该语句之前添加byte[] buffer = new byte[2048];。同时,为了防止内存泄漏,需要将Pen对象使用完毕后及时释放资源,可以使用using语句块来完成。
修改后的代码如下:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
//以下是正确内容
OpenFileDialog openFileDialog = new OpenFileDialog();
WaveFileReader waveFileReader;
DialogResult dialogResult = openFileDialog.ShowDialog();
waveFileReader = new WaveFileReader(openFileDialog.FileName);
waveViewer1.WaveStream = waveFileReader;
WaveFileChunkReader waveFileChunkReader = new WaveFileChunkReader();
waveFileChunkReader.ReadWaveHeader(waveFileReader);
byte[] buffer = new byte[2048];
waveFileReader.Read(buffer, 8, buffer.Length);
byte[] halfbuffer = new byte[1024];
// 将buffer1的内容平均除以2并复制到buffer2中
for (int i = 0; i < halfbuffer.Length; i++)
{
halfbuffer[i] = (byte)(buffer[i * 2] / 2 + buffer[i * 2 + 1] / 2);
}
//作业:使用GDI+把halfbuffer的数据绘制到panel里去。
}
public class chunk
{
public List<char> ID;
public int size;
public List<Byte> Data;
}
private void waveViewer1_Load(object sender, EventArgs e)
{
}
private void panel1_Paint(object sender, PaintEventArgs e)
{
byte[] buffer = new byte[2048];
byte[] halfbuffer = new byte[1024];
// 将buffer1的内容平均除以2并复制到buffer2中
for (int i = 0; i < halfbuffer.Length; i++)
{
halfbuffer[i] = (byte)(buffer[i * 2] / 2 + buffer[i * 2 + 1] / 2);
}
using (Pen pen = new Pen(Color.Black))
{
Graphics g = e.Graphics;
int panelHeight = panel1.Height;
int panelWidth = panel1.Width;
// Calculate the distance between each point
float pointDistance = (float)panelWidth / halfbuffer.Length;
// Scale the heights so they fit into the panel
float heightScaling = (float)panelHeight / 256;
// Draw the waveform
for (int i = 0; i < halfbuffer.Length - 1; i++)
{
float x1 = i * pointDistance;
float y1 = halfbuffer[i] * heightScaling;
float x2 = (i + 1) * pointDistance;
float y2 = halfbuffer[i + 1] * heightScaling;
g.DrawLine(pen, x1, y1, x2, y2);
}
}
}
}
相关推荐
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)